This invention has particular application to automatic lubrication systems for supplying lubricant to multiple points of lubrication at predetermined intervals and/or in predetermined amounts. Lincoln Industrial sells such automated systems under the Quicklub®, Centro-Matic®, and Helios® trademarks. The Quicklub® system includes a reservoir for holding a supply of lubricant, a stirrer for stirring the lubricant, and an electric or pneumatic pump for pumping lubricant from the reservoir to one or more progressive metering (divider) valves each of which operates to dispense lubricant to multiple points of lubrication. Reference may be made to U.S. Pat. No. 6,244,387, incorporated herein by reference, for further details regarding an exemplary Quicklub® system. The Centro-Matic® system is similar to a Quicklub® system except that lubricant from the pump is delivered through a single supply line to injectors each operating to dispense a metered amount of lubricant to a single lubrication point. Reference may be made to U.S. Pat. No. 6,705,432, incorporated herein by reference, for further details regarding an exemplary Centro-Matic® system. The Helios® system is a dual line system.
Grease manufacturers have developed grease formulations with extreme pressure additives for heavy industrial markets. These additives react with bearings under high loads to prevent metal-to-metal contact, thereby reducing wear on the bearings. The additives generally include solid particles blended into grease. In some embodiments, additives include molybdenum disulfide and calcium carbonate blended into the grease. Although these additives reduce bearing wear, they act as an abrasive in lubrication pumps. In particular, the additives wear the pistons in the pumps during repetitive back and forth pumping action under high pump pressures. Piston wear can prevent pumps from producing adequate pressures and dispensing grease. Thus, there is a need for systems and methods for predicting and estimating piston wear so corrective actions can be taken before the pumps fail.